Telephone-transmitter.



Patented Nov. 26, I90l.

W W DEAN TELEPHDNETRANSMITTER.

(Application filed Mar. 22, 1901.)

(No Model.)

javen fi? TH: uon'ms PETERS co. wmour UNITED STATES PATENT OFFICE.

WILLIAM W. DEAN, OF CHICAGO, ILLINOIS, ASSIGNOR TO KELLOGG SW ITCH-BOARD AND SUPPLY COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OFILLINOIS.

TELEPHONE-TRANSMITTER.

SPECIFICATION forming part of Letters Patent No. 687,499, dated November26, 1901.

, Application filed March 22, 190 l. $erial No. 52.276. (No model.)

To all whom it may concern.-

Be it known that I, WILLIAM W. DEAN, a citizen of the United States,residing at Chicago, in the county of Cook and State of Illinois, haveinvented a certain new and useful Improvement in Telephone-Transmitters,of

which the following is a full, clear, concise, and exact description,reference being bad to the accompanying drawings, forminga part of thisspecification.

My invention relates to a telephone-transmitter of the granular type, inwhich a body of granular carbon or similar material is interposedbetween two electrodes adapted to partake of relative movement to varythe resistance between the electrodes.

It is the object of my invention to provide a telephone of this typewhich will be simple and compact in structure and which will effectivelyprevent the packing of the granules, thereby overcoming an objectionwhich isincident to most of the granular telephones as commonlyconstructed heretofore.

In accordance with my invention I provide a suitable diaphragm adaptedto be vibrated by the vocal organs of the speaker, the diaphragmcarrying a suitable recess or chamber for the granules, in which chamberis located one of the electrodes of the telephone. Asupplementaldiaphragm is associated with the main diaphragm andperipherally attached thereto, the second electrode of the microphonebeing associated with said supplemental diaphragm in an intraperipheralpositionthat is, associated with the supplemental diaphragm within theperiphery thereof and preferably at the center of the supplementaldiaphragm. The supplemental diaphragm cooperates in maintaining thegranules within the chamber, and the electrode associated therewith ismounted in any suitable manner, so that as the main diaphragm vibratesthe electrode will partake of relative movement to vary the resistanceof the microphone. I preferably support the electrode which isassociated with the supplemental diaphragm upon a rigid abutment orsupport, as I find this structure to give the best results, although theemployment of a rigid abutment or support is not essential to theoperation of the telephone.

I have illustrated my invention in the accompanying drawings, in whichform carries the usual mouthpiece a and supports the inclosing casing aThe main diaphragm b carries upon the periphery the usual packing-ringb, of rubber or similar material, and is adapted to be yieldinglypressed against the face or support a, by means of the springs c 0,having pads, of rubber or similar material, upon the ends. Asillustrated, the diaphragm b has the central portion 19 laterallydeflected or displaced to form a recess or chamber 19 of the microphone,which preferably takes the form of a metal plate d, having a threadedshank d, which passes through a central opening in the part 5 upon whichthreaded shank a nut d is adapted to be screwed to securely bind theelectrode to the diaphragm. Upon the face of the plate (1 a carbon blockor disk (I is mounted, preferably by electroplating the face of thecarbon disk and then soldering the same to the plate (1. While Ipreferably form the electrode of carbon and metal, as above described,it will be under stood that the electrode may be formed in any otherpreferred manner. The side walls of the chamber may be covered withlacquer or suitable material to insulate the same from the granuleswithin the chamber, or they may be depended upon to constitute theelectrode, though not so eificieutly as with the construction described.Thesupplemcntaldiaphragm e, of mica or other suitable material, issecured at its periphery to the edge of the chamber by means of a ring eand the screws 6 e or in any suitable manner, the supplemental diaphragme thus serving to close the chamber. The supplemental diaphragm ecarries a central opening, through which the shank f, connected with theplate f, is adapted to pass. The shank f also passes through a bore inthe block g, which has an enlarged head 9. Anut g screws upon thethreaded end of the shank f and serves to clamp the Within this chamberis supported one of the electrodes .the supplemental diaphragm.

central portion of the supplemental diaphragm e-between the head g andthe plate 1. Upon the face of the plate f a carbon block or disk d ismounted in a manner similar to the mounting of the disk 01 The electrodeassociated with the supplement-a1 diaphragm is of less diameter than thechamber, so that the granules may rest not only betweenthe twoelectrodes, but also upon the exterior of the periphery of the electrodeassociated with A transverse support or bridge-piece h is mounted at theends upon the base a and carries at the center an opening to receive theshank of the block h, said block h being preferably rigidly secured tothe bar or support 71. The party may be adjusted in position within thebore of the block h and clamped in the adjusted position by means of theset-screw 72 When air-currents due to the voice impinge against the maindiaphragm b, said diaphragm is set in vibration, thereby causing theelectrode carried by the main diaphragm to approach the stationaryelectrode and to reccde therefrom to vary the resistance through themicrophone. Since the chamber containing the granules is carried uponthe main diaphragm, whereby the granules are subjected to continualvibration, the tendency of the granules to pack is effectivelyprevented.

I have mentioned carbon granules as the specific resistance-varyingmedium to be used i with this transmitter, because at present this seemsto be the best suited for practical use. ,There are, however, otherwell-known forms of comminuted conducting material the use of whichclearly lies within the scope ofmy invention.

While I have illustrated my invention in connection with the details ofconstruction which have been worked out for commercial purposes, it willbe understood that they arewhich is associated with the supplementaldiaphragm is susceptible of considerable variation without departingfrom the spirit of my invention, and many other changes could be madewhich will readilysuggest themselves to those skilled in the art.

Having described my invention, what I claim as new, and desire to secureby Letters Patent, is

1. In a telephone-transmitter, the combination with a suitablediaphragm, of a chamber for the granules carried thereon, an electrodewithin said chamber and moving with said diaphragm, a supplementaldiaphragm peripherally secured to said main diaphragm,

and a second electrode associated with said supplemental diaphragm in anintraperipheral position, substantially as described.

2. In a telephone-transmitter, the combination with a suitablediaphragm, of a chamber for the granules carried thereon, an electrodewithin said chamber and partaking of the movement of said diaphragm, asupplemental diaphragm peripherally connected with said diaphragm, asecond electrode associated with said supplemental diaphragm in anintraperipheral position, and an abutment for said second electrodemounted in a stationary position, substantially as described.

3. In a telephone-transmitter, the combination with a diaphragm having acentral portion relatively displaced to form a chamber for the granules,of an electrode within said chamber and partaking of the movement of thediaphragm, a supplemental diaphragm peripherally secured to the maindiaphragm and a second electrode associated with said supplementaldiaphragm in an intraperipheral position, substantially as described.

4. In a telephone-transmitter, the co mbin ation with the diaphragm, I),having the central portion, b laterally deflected to form a chamber forthe granules, of an electrode mounted within'said chamber and having ashank passing through an opening in said part, b, a fastening deviceengaging said shank, the supplemental diaphragm, e, the ring, 6', forsecuring the periphery thereof to the main diaphragm, b, the stationarysupport, h, the block, 9'', adjustably movable relatively to saidsupport, h, and the electrode carried upon said part; g, and associatedwith said supplemental diaphragm, substantially as described.

5. In a telephone-transmitter, the combination with a sound-receivingdiaphragm having a forwardly-deflected portion, of an electrodecarried-in said forwardly-deflected portion, and a second electrodeadapted to cooperate with said first-mentioned electrode throughthemedium of comminu ted conducting material, substantially asdescribed.

6. In a telephone-transmitter, the combination with a diaphragmcomprising a sheet of material having a portion laterally deflected toform a recess or chamber, of an electrode within the chamber and movingwith said diaphragm, a second electrode, a suitable support for saidsecond electrode, and comminuted material between the two electrodes andcooperating therewith, substantially as described.

'7; In a telephone-transmitter, the com bination with a diaphragmcomprising a sheet of material having a portion deflected to form arecess or chamber, of an electrode within the chamber and moving withthe diaphragm, a stationary support, a second electrode mounted on saidsupportand extending into said recess or chamber, and comminutedmaterial in said recess or chamber between said e1ectrodes,substantially as described.

too

8. In a telephone-transmitter, the combination with a suitablesound-receiving diaphragm carrying a laterally-deflected chamber for thegranules, of an electrode within said chamber and moving with saiddiaphragm, a supplemental diaphragm adapted to close said chamber, and asecond electrode associated with said supplemental diaphragm in anintraperipheral position, substantially as described.

9. In a telephone-transmitter, the combination with a metallic diaphragmcarrying a forwardly-deflected chamber, an electrode Within said chamberand having a shank passing through an aperture in the bottom thereof,means for securing said shank to the Wall of the chamber whereby theelectric circuit is completed therethrough, a second electrodecooperating with the first-mentioned electrode, and comminuted materialbetween said electrodes, substantially as described.

10. In a telephone-transmitter, the combination with a diaphragm havinga chamber for the granules carried thereon, of a supplement-a1 diaphragmperipherally secured to said main diaphragm, a block fitting against theouter face of said supplemental dia-\ phragm, a plate fitting againstthe inner face of said diaphragm, and means to clamp said plate andblock together upon the diaphragm, substantially as described.

11. In a telephone-transmitter, the combination with a main diaphragm, achamber or recess carried thereby, a supplemental diaphragm peripherallysecured to said main diaphragm, a block pressing against the outer faceof said supplemental diaphragm, a plate similarly located with referenceto the inner face of the supplemental diaphragm and having a shankextending through a bore in said block, means to secure the shank so asto clamp the plate and block together upon the said diaphragm, and asupport for the block, substantially as described.

12. In a telephone-transmitter, the combination with a diaphragm havinga central portion laterally deflected to form a recess or chamber, anelectrode in the chamber and movable therewith, a second electrode, asuitable support therefor, and comminuted material between saidelectrodes, substantially as described.

13. The combination with a vibratory member forming a chamber, of anelectrode adapted to vibrate therewith, a supplemental member to closesaid chamber, a second electrode associated with said supplementalmember and adapted to be rigidly mounted, and comminuted conductingmaterial within said chamber, substantially as described.

14. In a telephone-transmitter, the combination with a suitablediaphragm, of a chamber carried thereby, an electrode in said chamberand moving therewith, an independentlysupported electrode opposed tosaid first-mentioned electrode and having a piston like movementrelatively to said chamber, and comminuted material between saidelectrodes, substantially as described.

15. In a telephone-transmitter, the combination with a diaphragm, arecess or chamber carried thereby, a supplemental diaphragm, a blocksecured to the supplemental diaphragm, a support for the block, andmeans to secure the block in its support in any position, whereby theblock may be adjusted in its support by the vibration of the diaphragmand then secured in adjusted position, substantially as described.

16. In a telephone-transmitter, the combination with a suitablesound-receiving diaphragm, of a chamber for the granules carriedthereon, an electrode within said chamber and moving with saiddiaphragm, a supplemental diaphragm adapted to close said chamber, and asecond electrode associated with said supplemental diaphragm in anintraperipheral position, substantially as described.

17. In a telephone-transmitter, the combination with a suitablediaphragm, of a chamber for the granules carried thereon, an elec-'trode within said chamber and moving with said diaphragm, a supplementaldiaphragm' having its periphery secured to the edge of the chamber, andasecond electrode associated with said supplemental diaphragm in anintraperipheral position, substantially as described.

18. In a telephone-transmitter, the combination with a diaphragm havinga laterallydeflected chamber thereon, of an electrode in said chamberand movable therewith, a supplemental member, a second electrode associated therewith, said supplemental member being adapted to close saidchamber and permit the free relative vibration of said 'electrodes, andcomminuted conducting material within said chamber, substantially asdescribed.

19. In a telephone-transmitter, the combination with a cylindrical frontpiece, of a sound-receivin g diaphragm having its central portionforwardly displaced, an electrode mounted in said displaced portion ofthe diaphragm and adapted to partake of the movement of the center ofthe diaphragm, an abutmentor supporting-bridge rigidly secured to saidfront piece, a second electrode adapted to be rigidly mounted on saidabutment or bridge and opposing said first electrode, a resilient memberassociated with said second electrode, and comminuted material betweensaid electrodes and confined by said resilient member, substantially asdescribed.

In Witness whereof I have hereunto subscribed my'name in the presence oftwo witnesses.

. WILLIAM W. DEAN. \Vitnesses:

MELANOTHON R. NYMAN, W. CLYDE JONES.

